R. G. Silva’s scientific contributions

Esta revisão pretende efectuar uma abordagem aos conceitos de estabilidade e tracking, bem como resumir os principais resultados de estudos longitudinais sobre estabilidade da actividade física. Faz-se a distinção entre os diferentes tipos de estabilidade: estrutural, normativa ou da covariância, de nível ou das médias, e ipsativa. Aborda-se a problemática do tracking, da sua multiplicidade de significações e operacionalizações. Os principais resultados sobre a estabilidade da actividade física salientam, que na generalidade, os seus valores são baixos a moderados. Este quadro genérico coloca desafios à investigação de inúmeros pesquisadores, desde epidemiologistas a professores de educação física. ABSTRACT The main purposes of this paper is to review the concepts of stability and tracking, as well as the main results from longitudinal studies focusing on physical activity. We explain the different meanings of stability: structural, normative or covariance, level or means, and ipsative. We also look at tracking issues, its different meanings and ways of computation. The main results from physical activity studies do show that, in general, stability varies from low to moderate values. These results challenge researchers from different fields of study, from epidemiologists to physical education teachers.

Motor coordination level of school aged children (6-10 years) of the Azores Islands The purposes of this investigation were: (1) to characterize the develop- mental state of motor coordination in primary school children; (2) to identify differences between children of both genders; and to (3) identify the presence of insufficient motor coordination. Sample comprises 3742 children of both genders with 6 to 10 years of age. Motor coordination was evaluated with the test battery "Körperkoordinationstest für Kinder" (KTK). The battery comprises four tests: backward balance (ER), jumping sideways (SL), hopping on one leg (SM), and shifting platforms (TL). Factorial ANOVA (gender*age) was used to identify differences between boys and girls in each age. Discriminant function was used to test the presence of multivariate profiles of motor coordina- tion. It was found a performance increment with age in both genders in all items of test battery, and that boys had higher mean values than girls in all ages and in all items of the test battery, but in SL. Mean values of performance in all test items were lower than in other Portuguese and foreigner samples. Most of the children of both genders in all ages had a motor quotient in the interval of low coordination and coordination disorder. In both genders was noted a tendency for children of one age to have a lower profile of motor coordination than the one expected for their own age. These results showed that children of all ages had a low development of motor coordination.